Corkscrew



FIG. 1 is a perspective view of the corkscrew;

FIG. 2 is a front elevation view thereof (with the rear a mirror image thereof);

FIG. 3 is a right side view thereof (with the left side a mirror image thereof);

FIG. 4 is a top view thereof; and,

FIG. 5 is a bottom view thereof.

The broken lines represent unclaimed features and form no part of the claimed design. 

CLAIM The ornamental design for a corkscrew, as shown, and described. 